Lewis Hamilton is confident Mercedes is making progress during pre-season testing but stopped short of predicting anything more than points after his third day in the new car.

Hamilton set the fourth fastest time at Barcelona on Wednesday as he got back into the cockpit of the Mercedes for the first time since the Jerez test. He completed an impressive 121 laps and is confident his new team is gaining a better understanding of the W04.

"We haven't really put any updates on the car but we're definitely making steps forward in terms of our understanding of the set-up and the tyres," he said. "It's been a good day."

Asked to name a target at this stage, he said: "The realistic target is to finish races and get into the points."

He said there was still plenty to do ahead of the Australian Grand Prix in less than a month's time, but reiterated his admiration for Mercedes' work.

"I have a lot of work to do but I've got a great group of people behind me that are working. I'm sure they've been working hard over the years but immediately I've seen fantastic determination and effort going in and I really hope all that hard work pays off."